A. Field of the Invention
The present invention relates to a low-fat food product. More particularly, the present invention preferably relates to a baking flour and fat substitute that is low not only in triglycerides but also in mono- and diglycerides as well.
Preferably, the resulting flour-based food product is also all natural, cholesterol free, low in sodium, resistant to mold formation, and yet very easy and economical to manufacture, ship, and sell. An additional aspect is that the food product can be resistant to microwave-induced loss of palatability (texture and taste).
B. State of the Art
Conventional formulations of baked goods have long employed animal fat (such as lard and butter), vegetable fat, and egg yolks to provide certain important properties during mixing and baking and, afterwards, in the resulting baked food product. Animal fat, for example, typically renders flour dough much more creamy, flowable, and viscous. This makes the dough much less sticky and much easier to handle, particularly in high volume, commercial mixing machinery. The fat in the dough also helps reduce sticking of the baked product to a baking pan or other baking surface during the cooking step.
Fat is used in relatively high concentrations in pie crust to provide a crispy and quite flaky texture in the crust. Fat is used in lower concentrations in cookies and brownies to disperse and retain water in the body of a cookie or brownie while providing a crisp but not flaky outer crust. In addition, fat, which is an emulsifying agent, can provide moisture stabilizing and retaining effects that can significantly enhance shelf life of baked goods.
The use of animal fats in food products and baking, however, raises numerous problems the food industry has long sought to solve. The human body stores the fat as fat. Stored fat is relatively difficult for the body to process and is generally burned after all ready sources of carbohydrates are exhausted. As a result, fat adds to body weight and can exacerbate or cause many health problems.
Animal fat and egg yolks are also high in cholesterol. Cholesterol is widely known to contribute to a variety of health problems, such as high blood pressure and clogging of the arteries.
The food industry long ago discovered that substitution of vegetable oil or fat (such as corn syrup) for animal fat reduces cholesterol content, while enhancing resistance to rancidity of the resulting baked good. Vegetable oil nevertheless still is a triglyceride fat and processed as a fat by the human body. It also can have a significantly deleterious effect on the taste of the resulting baked good.
It is for this reason that vegetable fat is typically used in combination with other fat substitutes such as egg whites, mono- and diglycerides, and starches. All these substitutes can significantly affect the taste of the resulting product, requiring significant effort to reformulate a given baked good to minimize change of taste from the traditional recipe for the baked good.
In addition, mono- and diglycerides, although not presently classified as fats by the FDA, are nevertheless digested, stored, and processed by the human body in virtually the same fashion as ordinary triglyceride fats. Thus, it appears that mono- and diglycerides cause many of the same weight management and health problems brought about by consumption of the triglyceride through animal and vegetable fats and egg yolk.
There have been several attempts to incorporate dried or wet prunes, dates, and other sources of extracted pectin in order to obtain "low fat" baked goods. Examples of these types of solutions are reflected in: (i) "Just Like Shortenin'" by The Plumlife Co. of Madison, Conn.; (ii) the "Sunsweet Prune Paste/Powder Low Fat Recipes" of the Sunsweet Growers, Inc., Yuba City, Calif.; (iii) the report on "Utilization of Dried Plums in Reduced-Fat/Cholestrol-Free Bakery Products" by the California Prune Board, Pleasanton, Calif.; and (iv) the "Brownie, Fat Free. Low Sodium," by Greenfield Healthy Foods Co , Southport, Conn.
The pectin globules in these products (prunes, dates, and pectin extract) are known to function somewhat like, although by no means identically to, fat globules. In this regard, pectin does not have the same moisture stabilization and retention properties as fat or mono- or diglycerides. Also, by themselves, these sources of pectin can yield a chewy, grainy, and bitter (Ph adjusted) result.
For example, some of these techniques have utilized a variety of fat-like additives such as mono- or diglycerides (disclosed as "emulsifiers" in the Sunsweet Growers recipes and the California Prune Board report cited above). They have thus obtained foods that have been advertised as "low fat" under FDA rules but in reality include significant fat-like baking additives with their attendant complications and disadvantages for the consumer.
Other attempts at a solution using prunes, dates, or extracted pectins have required other additives, such as sorbitol, maltic acids, eggs, or soy lecithin. (See, e.g., the Plumlife Company and Greenfield Healthy Food Company products, and the California Prune Board report cited above.) These types of formulations affect taste, texture, and baking characteristics. They have involved substantial experimentation and reformulation of traditional recipes, have not provided 1:1 substitutes for flour, and frequently are not all-natural and do not yield acceptable taste, texture, or shelf life. (Id.; see also the Sunsweet Growers recipes cited above.)
In addition, many of these prior attempts at providing low-fat baked goods have nonetheless utilized fat on the cooking surface during the cooking step. (See the California Prune Board report and the Sunsweet Growers recipes.) One reason these methods utilize fat is because of "increased stickiness of the dough due to lack of shortening," i.e. fat in the dough itself. (See California Prune Board report at last page.) As noted in the California Prune Board report (last page), use of fat in this manner results in absorption of at least some fat in the resulting food product. Without such use of fat during baking of such formulations, the dough may stick to the cooking surface and require extra effort to remove it. (Id.)
Another problem is that traditional baked goods made with animal fats, vegetable fat, egg yolk, or mono- or diglycerides have not microwaved well. As explained in applicant Wolke's prior U.S. Pat. No. 5,104,669, entitled "Microwaveable Flour-Starched Based Food Product," issued Apr. 14, 1992 (the "669 Patent," which the applicants incorporate herein by reference), microwaving of such traditional mixtures frequently renders them unpalatable, with hardened, rubbery, or gummy crusts, and soggy, unevenly baked insides.
The invention of the '669 Patent solved the problem of microwave deterioration to a very significant degree. The '669 invention provides a flour-starch mixture suitable for use as a flour substitute in baked goods. The '669 Patent's flour substitute is called a "flour-starch" mixture consisting of about 85% to 35% flour, 15% to 60% high amylose starch, and 25% to 5% high amylopectin starch. The '669 Patent and its invention did not, however, eliminate the use of fats, fat-like substitutes such as mono- or diglycerides, or egg yolk.